Spiral welded pipe twisted guided wave detection method and spiral welded pipe twisted guided wave detection device adopting spiral energy converter

Abstract

The invention discloses a spiral welded pipe twisted guided wave detection method and a spiral welded pipe twisted guided wave detection device adopting a spiral energy converter. The guided wave frequency dispersion property of a spiral welded pipe is calculated through a semi-analytical finite element method so as to calculate twisted guided wave frequency of a parallel spiral welding line and a wave velocity thereof; the spiral energy converter is arranged by one circle along the spiral direction and is controlled by a guided wave detector to stimulate twisted guided wave; echoes are received after the guided wave is axially transmitted along the spiral welded pipe and meets defect reflection; and a defect position is determined according to a defect wave packet and a defect distance is calculated. According to the spiral welded pipe twisted guided wave detection method and the spiral welded pipe twisted guided wave detection device, a phenomenon that a spiral welding line signal continuously appears in the echoes when a traditional annular integrated magnetostriction energy converter is used for carrying out guided wave detection is eliminated, and the signal to noise ratio of the echoes is improved, so that a defect signal can be easy to extract, and the reliability of the guided wave detection of the spiral welded pipe is improved.

Description

technical field [0001] The invention relates to a non-destructive detection method for defects of a spiral welded pipe, in particular to a method and device for detecting a torsion-bending guided wave of a spiral welded pipe using a spiral transducer, and belongs to the technical field of non-destructive detection. Background technique [0002] Spiral welded pipe is a steel pipe made by rolling a steel strip into a tube blank according to a certain helical angle and welding the pipe seam. It has good weldability and crack resistance, and is widely used in long-distance pipelines. During the service process, the spiral welded pipe will be affected by factors such as corrosion and external force damage, resulting in various defects in the spiral welded pipe. If the defects in the spiral welded pipe cannot be found in time, it will lead to the leakage of the long-distance pipeline and endanger the safety of people and property. In order to avoid accidents caused by defects of ...

AI Technical Summary

Problems solved by technology

Since the position of the reinforcement projection of the spiral weld on the cross-section of the pipe is always changing, at any moment when the guided wave of the cylindrically symmetrically distributed wavefront passes through a helical weld with a pitch, the guided wave beam will be at a certain point of the helical weld with the pitch. Reflection occurs at this position, so that the weld signal continues to appear in the echo, resulting in a significant drop in the signal-to-noise ratio of the echo

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